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Subject: RE: [PATCH] SUNRPC: Prevent kernel stack corruption on long values of flush
Date: Thu, 18 Oct 2012 09:34:57 +0100
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thread-topic: [PATCH] SUNRPC: Prevent kernel stack corruption on long values of flush
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References: <1342476086-21638-1-git-send-email-levinsasha928@gmail.com> <20120718173913.GA1298@fieldses.org> <20120718200049.GA17964@umich.edu> <20120718203304.GA18540@redhat.com> <20120718205510.GA18374@umich.edu> <507EF918.5030004@panasas.com>
From: "David Laight" <David.Laight@ACULAB.COM>
To: "Boaz Harrosh" <bharrosh@panasas.com>, "Jim Rees" <rees@umich.edu>
Cc: "Dave Jones" <davej@redhat.com>, "J. Bruce Fields" <bfields@fieldses.org>,
        "Sasha Levin" <levinsasha928@gmail.com>, <Trond.Myklebust@netapp.com>,
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> ...
> long is always the same or bigger then a pointer
> (A pointer must always fit in a long)
> ...

Linux may make that assumption, but it doesn't have
to be true. 64bit windows still has 32bit long.
C99 inttypes.h defines [u]intptr_t to be an integral type
that is large enough to hold a pointer to any data item.
(That in itself is problematic for implementations that
encode multiple characters into a machine word and need
to use 'fat' pointers in order to encode the offset.)

	David

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